The present invention relates generally to optical actuator positioning devices, and particularly to two position optical actuator devices.
It is known in the art of positioning devices to move an optical element into and out of the path of a beam of electromagnetic radiation or particles, or to position a source such as a laser with respect to a target. However there is a need for a device wherein at the end of the optical element""s travel there is a minimum of vibration experienced by the optical element. Furthermore, for safety considerations, there is a need for a device which moves the optical element from a first position to a second position by means without the use of power, when the optical element is no longer restrained in the first position, such as when power to the device is cut or lost. For example, there is a need for an optical shutter system which moves a shield into the path of a beam line when power is lost. In other applications, there is a need for a device that can position a source emitting electromagnetic radiation or particles. This would be useful for positioning beam sources such as lasers or particle beam sources. For example, if the beam is focused on a target, moving the beam in the event of a power failure could prevent damage to the target. Such a device would also be useful where the flux emitted is not focused, such as in a radioactive sample being analyzed. For example, it would be useful to be able to move the source behind shielding in the event of a power failure. Where an instrument is being used to measure EM radiation or particles, it would useful for such a device to be able to move the instrument out of the flux in the event of a power failure so as to protect the instrument from damage.
It is therefore an object of the present invention to provide a two position optical actuator device that does not require power to move an optical element from a first position to a second position when the restraining means ceases to hold the optical element in the first position. Such situations include but are not limited to when the restraining means ceases to receive power, a malfunction or failure of the restraining means, or scenario where the restraining means loses contact with the driver bar.
It is a further object of the present invention to provide a two position optical actuator device that imparts a minimum amount of vibration to an optical element when the optical element is moved from a first to second position.
It is a further object of the present invention to provide a two position optical actuator device that can move a variety of optical elements, including EM radiation or particle sources, EM radiation or particle instruments, elements capable of reflecting, absorbing or transmitting EM radiation or particles, and targets or workpieces upon which the EM radiation or particles will act.
According to one aspect of the present invention, there is provided a two position optical actuator device, comprising a mounting base; an actuation arm having a first end, a second end, and a middle region, said middle region being rotatably connected to said mounting base, said first end including an elongated opening, said second end having an attached optical element; a driver bar for driving said actuation arm between actuation arm first and second positions, said driver bar having a first end rotatably connected to said mounting base and a second end on which is mounted a bearing for engaging and traveling within said elongated opening, so that when said driver bar pivots in a given direction said actuation arm is driven in an opposite rotational direction by said bearing; powered means for holding said driver bar in a driver bar first position which maintains said actuation arm in said actuation arm first position (and optical element first position); and non-powered means for moving said driver bar to a driver bar second position when said driver bar is not restrained by said powered means, so that said actuation arm is driven to said actuation arm second position (optical element second position). The optical element may be a source, an instrument, an element capable of reflecting, transmitting or absorbing EM radiation or particles, or a target or workpiece upon which EM radiation or particles impinge.
According to another aspect of the present invention the optical element interacts with the flux from a source (preferably a beam source) of EM radiation or particles. In one aspect, the optical element is initially held outside of the path of the flux by the powered means. The optical element is moved into the beam""s path by the non-powered means when the driver bar is not restrained by the powered means. In another aspect the optical element is initially held in the path of the beam by the powered means. The optical element is moved out of the beam""s path by the non-powered means when the powered means ceases to receive power.
In a further aspect of the present invention, the optical element is a source (preferably beam source) of EM radiation or particles, in which at least a portion of whose emission impinges upon a second optical element. In one aspect, the second optical element receives flux from the source when the driver bar is in the first position, and none when the driver bar is in the second position. In another aspect, the second optical element receives no flux in the driver bar first position, and flux in the driver bar second position.
Other objects and features of the present invention will be apparent from the following detailed description of the present invention.